code: def test_change_field_transform():
      one_added = transform_schema(
          TestSchema,
          TransformSpec(
              lambda x: x,
              edit_fields=[
                  UnischemaField("double", np.float16, (), None, False)
              ],
          ),
      )
      assert one_added.fields["double"].numpy_dtype == np.float16
  
file_path: petastorm/petastorm/tests/test_transform.py
imports: import numpy
  import pytest
  from petastorm.transform import edit_field, transform_schema, TransformSpec
  from petastorm.unischema import Unischema, UnischemaField
label_desc: Use image node_id 5 for calling a global function with example usage: test_change_field_transform() without return types